P91-1.5kLi: 1500 VA Lithium Iron Phosphate (LFP) UPS
Online double-conversion lithium protection at 1500 VA / 1350 W, in a 2U chassis 15.1 inches deep and 25.6 lbs. LiFePO₄ batteries rated for up to 15 years, 3 to 4 times the life of lead acid.
Of the online 1.5 kVA lithium units compared here, it is the shallowest and the lightest, with the longest warranty. If runtime is the priority, the P91-2kLi is the better fit.
Why the P91-1.5kLi stands out
15.1 inches of rack depth, against 17.7 inches for the Eaton 9PX and 18.5 inches for the Vertiv GXT5Li.
25.6 lbs, against 35.5 to 43 lbs for the Eaton, Vertiv and APC 1.5 kVA lithium models.
Up to 15-year design life and 3,000–5,000 cycles. Eaton rates its 9PX lithium battery at 8 years float life.
The Eaton, Vertiv and APC models compared here are rated to 40 °C.
Back to 90% in about 1.5 hours, against about 2 hours for Vertiv and up to 3 hours for Eaton and APC.
Eight NEMA 5-15R receptacles, including a controllable bank for load shedding or remote reboot of that group.
Electronics and lithium battery (USA and Canada). Reduced to 2 years in 40–50 °C environments; 2 years depot repair elsewhere.
Connected equipment is covered up to $50,000 in the USA and Canada. Register within 10 days.
Qualifies for U.S. government, education and public-sector procurement as standard.
Smaller and lighter, or longer runtime
At 1.5 kVA the choice is a real trade-off. The Eaton and Vertiv carry more battery and run longer; the P91-1.5kLi is shallower, lighter, rated for more heat and backed longer. Choose by what the rack and the load need.
Where the P91-1.5kLi leads: the shallowest and lightest of the online models, a 6-year full warranty, the fastest recharge, operation to 50 °C and TAA compliance as standard. Where it doesn’t: runtime, where the Eaton and Vertiv run longer. For more runtime, see the P91-2kLi.
P91-1.5kLi at a glance
View the P91 Li datasheet » Full P91 Li specifications and runtimes »
How the P91-1.5kLi compares at 1.5 kVA
| Feature | Xtreme P91-1.5kLi | Eaton 9PX1500RT-L | Vertiv GXT5LI-1500LVRT2UXL | APC SMTL1500RM3UCNC |
|---|---|---|---|---|
| Output capacity | 1500 VA / 1350 W | 1500 VA / 1350 W | 1500 VA / 1350 W | 1500 VA / 1350 W |
| Topology | Online double-conversion | Online double-conversion | Online double-conversion | Line-interactive |
| Rack height | 2U | 2U | 2U | 3U |
| Depth | 15.1″ rack (16.1″ with bezel) | 17.7″ | 18.5″ | 11.9″ |
| Weight | 25.6 lbs | 35.5 lbs | 39.7 lbs | 43 lbs |
| Runtime at full load (1350 W) | 8 min | About 11 min | 14 min | About 5 min |
| Runtime at half load (675 W) | About 17 min | About 22 min | 28 min | Not published for this model |
| Recharge | About 1.5 h to 90% | Under 3 h to 90% | About 2 h | About 3 h |
| Max operating temp | 50 °C | 40 °C | 40 °C | 40 °C |
| Battery life rating | Up to 15 years | 8 years float at 25 °C | Up to 3× VRLA | 8–10 years |
| Warranty | 6-year full | 5-year | 5-year | 5-year |
| TAA compliant | Yes, standard | No (TAA version is a separate SKU) | No (TAA version is a separate SKU) | No |
Eaton, Vertiv and APC are trademarks of their respective owners and are referenced here for factual comparison only. Competitor specifications are based on published manufacturer and reseller data and are subject to change; verify current figures before purchase. Eaton figures are from the Eaton 9PX Lithium-Ion user guide (Rev 08) and Eaton’s online runtime chart (approximate). Vertiv figures are from Vertiv’s published specifications as listed by Dell. APC runtime is from a reseller listing. Competitor depths are as published; the P91-1.5kLi figure is rack-mounting depth. APC also offers a lifetime Equipment Protection Policy on its Smart-UPS SMTL line. Competitor data checked October 2026.
See detailed head-to-head comparisons →Where the P91-1.5kLi fits
Comparing other sizes? See the P91-1kLi 1000 VA, P91-2kLi 2000 VA and P91-3kLi 3000 VA comparisons.
P91-1.5kLi: frequently asked questions
How does the P91-1.5kLi compare with other 1.5 kVA lithium UPS?
How much runtime does the P91-1.5kLi give?
Is the P91-1.5kLi online or line-interactive?
How deep and heavy is it?
Is the P91-1.5kLi TAA compliant?
What warranty and protection come with it?
When should I choose the 2 kVA instead?
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